Lifetime Spectroscopy (eBook)

10/99 "Gustav-Mie-Preis" awarded for the diploma thesis by the Faculty of Physics at Albert-Ludwigs-University Freiburg 09/99 – 05/04 PhD thesis in physics at Fraunhofer ISE and University of Konstanz: "Lifetime spectroscopy as a method of defect characterization in silicon for photovoltaic applications" (overall grade: summa cum laude) 08/95 – 01/97 Undergraduate assistant at Fraunhofer ISE in the area of solar cell characterization 12/98 – 08/99 Research assistant at Fraunhofer ISE 1. in the department of solar cells – materials – technology 2. in the department of thermal optical systems 06/04 – today Research assistant at Fraunhofer ISE

Preface 7
Contents 10
Abbreviations, acronyms and symbols 15
Abbreviations and acronyms 15
Arabic symbols 16
Greek symbols 22
Introduction 25
Motivation 25
Aims and outline 27
References 28
1. Theory of carrier lifetime in silicon 29
1.1 Introduction 29
1.2 Fundamentals 1: basic and advanced models for the fundamental semiconductor quantities 30
1.3 Fundamentals 2: generation, recombination and carrier lifetime 55
1.4 Carrier recombination mechanisms 56
1.5 Effective lifetime and the separation of bulk lifetime 75
1.6 Chapter summary 79
References 80
2. Lifetime measurement techniques 83
2.1 Introduction 83
2.2 Quasi-steady-state photoconductance technique ( QSSPC) 85
2.3 Microwave-detected photoconductance decay technique ( MW- PCD) 87
References 92
3. Theory of lifetime spectroscopy 93
3.1 Introduction 93
3.2 General analysis of possibilities and restrictions 95
3.3 Injection-dependent lifetime spectroscopy (IDLS): advanced analysis 115
3.4 Temperature-dependent lifetime spectroscopy: improved standard analysis and its limitations 171
3.5 Temperature-dependent lifetime spectroscopy: superposed effects and advanced analysis 201
3.6 Combination of the results from TDLS and IDLS: combined DPSS analysis 252
3.7 Temperature- and injection-dependent lifetime spectroscopy (T-IDLS) 255
3.8 Chapter summary and conclusion 272
References 277
4. Defect characterization on intentionally metal-contaminated silicon samples 280
4.1 Introduction 280
4.2 Experimental details 282
4.3 Molybdenum 308
4.4 Titanium 326
4.5 Nickel 349
4.6 Iron 359
4.7 Detailed comparison of results 403
4.8 Chapter summary 414
References 415
5. The metastable defect in boron- doped Czochralski silicon 419
5.1 Introduction 419
5.2 Analysis I: major components 421
5.3 Analysis II: quantitative correlation with different impurities 425
5.4 Analysis III: mechanism of defect transformation 437
5.5 Analysis IV: electronic structure of the Cz defect 447
5.6 Reduction of the Cz-specific defect concentration 458
5.7 Material quality and realistic prediction of solar cell performance 468
5.8 Chapter summary 477
References 479
Summary and further work 483
Theory of lifetime spectroscopy: physical understanding and implementation 484
Experiment: lifetime spectroscopic study of intentionally metal- contaminated samples 486
Experiment: study of the metastable defect in Czochralski silicon 489
Relevance of the results and outlook 491
References 492
Zusammenfassung und Ausblick 493
Theorie der Lebensdauerspektroskopie: Physikalisches Verständnis und technische Umsetzung 494
Experiment: Lebensdauerspektroskopische Untersuchungen an gezielt metallisch verunreinigten Proben 497
Experiment: Untersuchung des metastabilen Defektesin Czochralski-Silizium 500
Relevanz der Ergebnisse und Ausblick 503
Literatur 504
Index 505